Oppo PM3 Review (Closed Back Headphone)

[Maiky76]

This is a review and detailed measurements of the Oppo PM3 closed back planar magnetic headphone. It is on kind loan from a member. The PM3 is discontinued but seems to have quite a following and hence the reason I wanted to test it. Originally it cost US $399 but I see used prices from $500 up to $800. Typical of Oppo products, it holds its value well and even appreciates!

I am not a fan of the look of the cups but otherwise, there is a nice luxury feel and look to this headphone especially in white:

View attachment 144414

A 3.5 mm cable connects at both ends which is convenient. Note however that you need a slim fitting one at the headphone side. The cable supplied has a larger one at one end which would not fit right on the headphone until I reversed it.

The cups are small and I can feel them on my ears. The softness of the super supple pads help. Width and length of the cup inside dimensions are 60x40mm. Depth is 20mm.

Noise isolation is very good. It would block almost 80% of the noise from my Audio Precision's fan. Best noise cancelling headphones land at 95%+ and less good ones at 90% so this is very good.

Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I confirm the approximate accuracy of the measurements using Equalization and listening tests. Ultimately headphone measurements are less exact than speakers mostly in bass and above a few kilohertz so keep that in mind as you read these tests. If you think you have an exact idea of a headphone performance, you are likely wrong!

Fitment on the fixture was challenging even though the cups easily covered the artificial ear on my measurement fixture. This resulted in fairly large variations in bass response. I got the two channels to match which is a good sign but still, keep in mind the cautions above in bold.

Oppo PM3 Measurements
As usual we start with the headphone frequency response as comparison to our preference curve:

View attachment 144415

First thing that stands out is the hump between 60 and 300 Hz. Other measurements show it less pronounced. And if I lowered the levels, I could make it less so even here. Listening tests have to confirm whether it is this exaggerated or not. Below and above this hump, we have surprisingly good compliance with our target. Response is "dirty" however with a number of kinks, likely caused by resonances. We have a bit of deficiency between 3 and 4 kHz and exaggerated peak around 7 to 8 kHz. Overall, this is not half bad.

Here is the relative response for equalization purposes:

View attachment 144416

Distortion is exceptionally low at bass frequencies especially as we consider that we already have enough or even too much energy there:

View attachment 144417

Unfortunately there are a lot of resonant peaks in higher frequencies. These could be the driver, the enclosure, or both. If you go back to the frequency response measurements, you can see traces of the same there.

Here it is in absolute log form:
View attachment 144418

Group delay doesn't tell us much except maybe confirming a resonance around 2 kHz:

View attachment 144419

Impedance is flat and low like most planar magnetics:

View attachment 144420

Sensitivity is above average so should not be hard to drive:
View attachment 144421

Oppo PM3 Listening Tests and Equalization
Some people accuse me of liking "bass." There is no better proof of this being wrong than me saying I did not at all like the bass response in the PM3. It is bloated. What I like is sub-bass response where there is almost never too much of a good thing. What is here is way too much and too high of a frequency which overwhems the tonality of the rest of the headphone. Add to that the lack of lower treble energy and the sound is not to my liking at all. Everything you play has some amount of "hmmmm" bass to it, whether it should or not.

So I pulled out the EQ and went after the three area of concern:

View attachment 144422

Once again I used dual filters to shape the response for bass (and amounts visually adjusted and hence the fractions). Measurements were correct in the level and magnitude of bass error. With this correct, deep bass is now a delight and the rest of the tonality gets to shine, well with the addition of the two filters.

Spatial qualities are good post EQ. I give it B+.

I am still listening them as I type this -- a sign of being happy with the sound of the headphone.

Conclusions
It is always nice to test "iconic" products and the Oppo PM3 is one. I can see some of the appeal it has in compliance with the Harman target in sub-bass and midrange. Exceptionally low distortion in bass helps with the clarity and clean sound here. This said, I can't listen to it without EQ. There is just too much boominess and missed sparkle in the lower treble.

I am happy to recommend the Oppo PM3 with Equalization. It is a pass for me without but it is not offensive for every day listening like some headphones are.

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As always, questions, comments, recommendations, etc. are welcome.

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Hi,

Here are some thoughts about the EQ.

Notes about the EQ design:

• The average L/R is used to calculate the score.
• The resolution is 12 points per octave interpolated from the raw data (provided by @amirm)
• A Genetic Algorithm is used to optimize the EQ.
• The EQ Score is designed to MAXIMIZE the Score WHILE fitting the Harman target curve with a fixed complexity.
  This will avoid weird results if one only optimizes for the Score.
  It will probably flatten the Error regression doing so, the tonal balance should be more neutral.
• The EQs are starting point and may require tuning (certainly at LF).
• The range around and above 10kHz is usually not EQed unless smooth enough to do so.
• I am using PEQ (PK) as from my experience the definition is more consistent across different DSP/platform implementations than shelves.
• With some HP/amp combo the boosts and preamp gain need to be carefully considered to avoid issues
• Not all units of the same products are made equal. The EQ is based on the measurements of a single unit.
• YMMV with regards to the very unit you are trying this EQ on.

Good L/R match.

I have generated one EQ, the APO config file is attached.

Score no EQ: 56.2
Score Armirm: 91.0
Score with EQ: 94.4

Oppo PM3 APO EQ Flat@HF 96000Hz
August022021-102518

Preamp: -3.5 dB

Filter 1: ON PK Fc 112.69 Hz Gain -5.20 dB Q 1.30
Filter 2: ON PK Fc 223.77 Hz Gain -3.94 dB Q 0.47
Filter 3: ON PK Fc 368.10 Hz Gain 3.87 dB Q 2.00
Filter 4: ON PK Fc 3259.44 Hz Gain 3.65 dB Q 1.99
Filter 5: ON PK Fc 7301.67 Hz Gain -5.39 dB Q 3.92

 

[Robbo99999]

Hi,

Here are some thoughts about the EQ.

Notes about the EQ design:

• The average L/R is used to calculate the score.
• The resolution is 12 points per octave interpolated from the raw data (provided by @amirm)
• A Genetic Algorithm is used to optimize the EQ.
• The EQ Score is designed to MAXIMIZE the Score WHILE fitting the Harman target curve with a fixed complexity.
  This will avoid weird results if one only optimizes for the Score.
  It will probably flatten the Error regression doing so, the tonal balance should be more neutral.
• The EQs are starting point and may require tuning (certainly at LF).
• The range around and above 10kHz is usually not EQed unless smooth enough to do so.
• I am using PEQ (PK) as from my experience the definition is more consistent across different DSP/platform implementations than shelves.
• With some HP/amp combo the boosts and preamp gain need to be carefully considered to avoid issues
• Not all units of the same products are made equal. The EQ is based on the measurements of a single unit.
• YMMV with regards to the very unit you are trying this EQ on.

Good L/R match.

I have generated one EQ, the APO config file is attached.

Score no EQ: 56.2
Score Armirm: 91.0
Score with EQ: 94.4

Oppo PM3 APO EQ Flat@HF 96000Hz
August022021-102518

Preamp: -3.5 dB

Filter 1: ON PK Fc 112.69 Hz Gain -5.20 dB Q 1.30
Filter 2: ON PK Fc 223.77 Hz Gain -3.94 dB Q 0.47
Filter 3: ON PK Fc 368.10 Hz Gain 3.87 dB Q 2.00
Filter 4: ON PK Fc 3259.44 Hz Gain 3.65 dB Q 1.99
Filter 5: ON PK Fc 7301.67 Hz Gain -5.39 dB Q 3.92

View attachment 144975

How come you didn't EQ the bass accurately to the curve below 100Hz?

 

[Maiky76]

How come you didn't EQ the bass accurately to the curve below 100Hz?

I suspect the notch is caused by the ear-cushion/headband spring/damping and the mass of the ear cup itself resonance.
Probably highly dependent on the actual fitting on the user head.

 

[Weebster]

Excellent point,
I can confirm this. I own the PM-3 (though nowadays one of my daughter uses it), the pads don't last a year and need to be replaced by newly bought pads at least once a year.

You are right that the cause is the use of protein (fake) leather. I also own various bluetooth headphones (AKG, Audio Technica, Parrot...) with protein leather, and when used regularly the pads also don't last a year (My wife and my several children also intensively use headphones, so this gives more experiences).

The use of the so-called protein "leather" may be strongly demanded for ideological reasons by vegan activists, who are very vocal about it (I can remember some fanatics who were raging against the Focal Stellia at head-fi because of the use of genuine leather), for real use my experience is that it is worthless, absolutely no match against real leather. I think that one should be careful about this (being very cautious to avoid fake leather pads), the more so for expensive headphones. I remember reading several times on the Hifiman Susvara thread at head-fi that some people complained that the pads of their $ 6000 Susvaras would not last longer than six months of their wearing them...

My experience is the same. I strongly dislike "vegan leather" or pleather on any item that is meant to last as the covering/fake leather degrades rather quickly. It is not just Oppo.

 

[somebodyelse]

My experience is the same. I strongly dislike "vegan leather" or pleather on any item that is meant to last as the covering/fake leather degrades rather quickly. It is not just Oppo.

That's an unwarranted blanket statement - there are good and bad synthetics, and Oppo have chosen to use a bad one. Amara has been used in mainstream sailing gloves for 30+ years now, and it's nothing to do with being vegan in that use - it holds up as well as leather, and it's easier to look after. Headphone pads have an easy life in comparison.

 

[Weebster]

That's an unwarranted blanket statement - there are good and bad synthetics, and Oppo have chosen to use a bad one. Amara has been used in mainstream sailing gloves for 30+ years now, and it's nothing to do with being vegan in that use - it holds up as well as leather, and it's easier to look after. Headphone pads have an easy life in comparison.

As a statement summarizing my personal experience and therefore my subjective opinion based on that personal experience I believe it is completely warranted. I have very few leather items in my household. I much prefer microfiber (which is what Amara appears to be) or mesh as they both breath better and last longer in my experience. I have yet to come across a quality synthetic "leather". Bonded leather, which is what the majority of mass market leather products are made of, also typically does not have a long life span. I typically look for "genuine leather" or some alternative that does not attempt to simulate leather. That said, I do have several items with the vegan "leather" such as the Status Audio ANC Flagship. It's just not my preference.

 

[bidn]

That's an unwarranted blanket statement - there are good and bad synthetics, and Oppo have chosen to use a bad one. Amara has been used in mainstream sailing gloves for 30+ years now, and it's nothing to do with being vegan in that use - it holds up as well as leather, and it's easier to look after. Headphone pads have an easy life in comparison.

Why do you deny Weebster's sharing of his own experience with the fake leather of his headphones as an unwarranted blanket statement? I can't believe you have used Weebster's personal headphones, so if someone is making unwarranted blanket statement, it would be you by denying his experience while you have no experience of his personal headphones. Strange attitude, so much unfair that I felt I needed to defend Weebster. And for this, isues of subjectivity (like with audiophile tonality perception) do not apply, because the degradation of fake leather earpads is not the subject of a visual illusion (and can also be verified by touch.)
Moreover we were and should only talking about headphones. So coming back to the subject of headphones, if you want to argue in favour of fake leather earpads, an on-topic interesting point would be:
Can you name any headphones with fake leather whose quality (resistance to abrasion and to chemical attacks such as those caused when putting them on and when wearing them around the human ears) equals that of genuine leather, unlike the poor and normal (re. headphone earpads) fake leather used by the Oppo's PM-3 (the headphones being the subject of the present topic)?

 

[somebodyelse]

As a statement summarizing my personal experience and therefore my subjective opinion based on that personal experience I believe it is completely warranted. I have very few leather items in my household. I much prefer microfiber (which is what Amara appears to be) or mesh as they both breath better and last longer in my experience. I have yet to come across a quality synthetic "leather". Bonded leather, which is what the majority of mass market leather products are made of, also typically does not have a long life span. I typically look for "genuine leather" or some alternative that does not attempt to simulate leather. That said, I do have several items with the vegan "leather" such as the Status Audio ANC Flagship. It's just not my preference.

It looks like we're quibbling over the definition of "vegan leather" then - I include the microfiber based materials in that group since they're often sold as leather or suede alternatives suitable for vegans. Exclude them and you exclude most, perhaps all, of the good ones I've seen so far. I'm with you on the rest.

 

[zvukofor]

What i really do love in PM-3 is low THD, plus only 2 points in FR needs correction and it is cutting only.
I use it for work at studio for recording, mixing, as a main reference headphones.
They do really perform much better than Sennheiser HD600/650, which are used very frequently at the studios.
I must admit working on them "translates" very well to a good tuned room with full range monitors (PMC IB1S and B&W 8xx series). Means i need no adjustments coming from working on headphones to speakers, besides compensating a little bit for diffused HF and physical LF effects of a speakers in room.

I've replaced vegan pads with custom leather ones that was made for Sony 7506 - they're of the same size.
Damn vegans and lead-free environmentalists actually do more harm to nature - leather lasts so much longer! So do Sn/Pb soldered PCBs...no wonder NASA still uses it! I do love everything environment-friendly, i do hate HDPE/PET packaging for every small thing in a shops, but man, leather?...

 

[Norwood]

lol at some of these comments. The resale value on these speaks for itself.

6+ years and still going strong. Sent to oppo once for new pads and a new headband.

Back on head-fi these were considered too lean on the bass. Oh well. EQ has always been required but they respond to EQ better than anything I’ve heard, which shows up in the measurements in THD especially in the low end. Using the idsd micro black label and EQ, I can get these vibrating on my head with no distortion. PM3 are excellent for music, gaming (the semi open pm2 is extremely underrated gaming headphone), and movies/tv. Plus you can use them in the studio as @zvukofor mentioned. True closed back all arounders. The low power requirements are nice but scales so good because planar. I run it on turbo mode on the BL.

Shown here with ibasso dx228ex + forza 4.4 cable.

 

[roog]

I had to replace the ear pads on my PM3's after a couple of years of occasional use, which I found to be disappointing.
I opted for a third party set of replacement pads which are holding up ok after a year of similar light use.
I do wonder whether 'hair products' might be an influence in the seemingly short life of pads, in may case hair gel?
I have only just noticed that the underside of the headband is starting to go after 5 years. That doesn't look quite as easy to replace.

 

[TheHighContemplator]

This headphone can’t hold a candle to the Dan Clark Aeon RT closed headphone.

It’s not close either and I’ve listened to both extensively. I sold my Oppo Pm3’s a few years ago . Good riddance .

Based on @amirm 's recomendation, I have the DCA ARTC's on the way to me from Drop. Your comment made me even happier, even it is anecdotal. Cheers!

 

[lordhumungous]

Based on @amirm 's recomendation, I have the DCA ARTC's on the way to me from Drop. Your comment made me even happier, even it is anecdotal. Cheers!

For the money , this is a fantastic headphone. I removed the white insert as I thought it muffles the clarity some.

 

[lordhumungous]

lol at some of these comments. The resale value on these speaks for itself.

6+ years and still going strong. Sent to oppo once for new pads and a new headband.

Back on head-fi these were considered too lean on the bass. Oh well. EQ has always been required but they respond to EQ better than anything I’ve heard, which shows up in the measurements in THD especially in the low end. Using the idsd micro black label and EQ, I can get these vibrating on my head with no distortion. PM3 are excellent for music, gaming (the semi open pm2 is extremely underrated gaming headphone), and movies/tv. Plus you can use them in the studio as @zvukofor mentioned. True closed back all arounders. The low power requirements are nice but scales so good because planar. I run it on turbo mode on the BL.

Shown here with ibasso dx228ex + forza 4.4 cable.
View attachment 146925

Have you listened to the Dan Clark Rt closed? Its not even close my friend.

 

[Ashimaru]

Just found Oppo PM-3 measurements from Speakerphone.

 

[SpaceMonkey]

Just found Oppo PM-3 measurements from Speakerphone.

Looks pretty close to my own own experiences with both.

 

[Ashimaru]

Found Oppo PM-3 measurements with B&K 4153, looks similar to Amirm measurements.

 

[Roen]

lol at some of these comments. The resale value on these speaks for itself.

6+ years and still going strong. Sent to oppo once for new pads and a new headband.

Back on head-fi these were considered too lean on the bass. Oh well. EQ has always been required but they respond to EQ better than anything I’ve heard, which shows up in the measurements in THD especially in the low end. Using the idsd micro black label and EQ, I can get these vibrating on my head with no distortion. PM3 are excellent for music, gaming (the semi open pm2 is extremely underrated gaming headphone), and movies/tv. Plus you can use them in the studio as @zvukofor mentioned. True closed back all arounders. The low power requirements are nice but scales so good because planar. I run it on turbo mode on the BL.

Shown here with ibasso dx228ex + forza 4.4 cable.
View attachment 146925

How did you send this to Oppo to refurbish the headband and earpads?

 

[Remlab]

[email protected]​